A team of scientists at the University of Utah has proposed that the unusual pattern of genetic diseases seen among Jews of central or northern European origin, or Ashkenazim, is the result of natural selection for enhanced intellectual ability.

The selective force was the restriction of Ashkenazim in medieval Europe to occupations that required more than usual mental agility, the researchers say in a paper that has been accepted by the Journal of Biosocial Science, published by Cambridge University Press in England.

The result is almost certain to set off a firestorm, especially amongst the multicultural/PC left which denies any innate human differences (especially in regard to intelligence), and will likely go apoplectic at the suggestion that one group may have a genetic advantage over another. In the wake of the controversy over Harvard President Larry Summer's remarks over the representation of women in science and mathematics earlier this year, the new study promises to cause a furor worthy of 1994's publication of The Bell Curve.

The hypothesis advanced by the Utah researchers has drawn a mixed reaction among scientists, some of whom dismissed it as extremely implausible, while others said they had made an interesting case, although one liable to raise many hackles.

"It would be hard to overstate how politically incorrect this paper is," said Steven Pinker, a cognitive scientist at Harvard, noting that it argues for an inherited difference in intelligence between groups. Still, he said, "it's certainly a thorough and well-argued paper, not one that can easily be dismissed outright."

Intriguingly the study posits a link between Ashkenazi intelligence and several genetic diseases known to afflict predominately people of Askenaze descent.

In both cases, the Utah researchers argue, evolution has had to counter a sudden threat by favoring any mutation that protected against it, whatever the side effects. Ashkenazic diseases like Tay-Sachs, they say, are a side effect of genes that promote intelligence.

The explanation that the Ashkenazic disease genes must have some hidden value has long been accepted by other researchers, but no one could find a convincing infectious disease or other threat to which the Ashkenazic genetic ailments might confer protection.

A second suggestion, wrote Dr. Jared Diamond of the University of California, Los Angeles, in a 1994 article, "is selection in Jews for the intelligence putatively required to survive recurrent persecution, and also to make a living by commerce, because Jews were barred from the agricultural jobs available to the non-Jewish population."

The Utah researchers have built on this idea, arguing that for some 900 years Jews in Europe were restricted to managerial occupations, which were intellectually demanding, that those who were more successful also left more offspring, and that there was time in this period for the intelligence of the Ashkenazi population as a whole to become appreciably enhanced.

The full text of the paper ("A Natural History of Ashkenazi Intelligence") can be found here.